CONSUMER watchdogs have pledged to step up the fight to ensure credit card holders aren't duped by misleading advertising campaigns.

Barclaycard was forced into a humiliating climb-down by the Office of Fair Trading over its "zero per cent forever" credit card offer, last week.

The OFT said the Barclaycard advertising was "highly misleading" in that the zero per cent rate was, in fact, only available on balance transfers and only if the consumer used the card to make purchases which attract interest at the higher standard rate.

Monthly payments by the consumer clear the balance transfer first and so the consumer cannot keep the transferred balance at zero per cent for ever.

The Barclaycard adverts stated, in large type, that zero per cent APR was to be offered forever, although most explained in smaller type this related only to balance transfers and the rate only applied if the cardholder spent £50 or more each month; otherwise a rate of 6.9 per cent applied.

Elsewhere, and with less prominence and clarity, the adverts stated the monthly payments would be used to meet the transferred balance first. All new purchases incur interest charges in line with the rate stated on the advertisement - 17.9 per cent APR.

Frances Harrison, head of research at the National Consumer Council, said: "Tighter credit laws are now long overdue. If Trading Standards had more resources to better police credit card companies, such as Barclaycard, this kind of situation would never happen.

"More importantly, if we had a compulsory `honesty box' system for all credit card promotions, Barclaycard is unlikely to have got away with their zero per cent deception for so long."

Ashleye Sharpe, head of Money Research, at Which?, said: "We are pleased to see the OFT coming down hard on the misleading marketing tactics surrounding Barclaycard's new deal.

"They target people who are trying to pay off their debts, and yet the conditions of the deal trap them into running up further debt which is charged at a much higher rate and cannot begin to be cleared until the balance transfer is paid off."